Singapore -– The answers are in for “burning questions” posted online in response to the SDP’s invitation to Ask Paul Anything (APA), referring to its Chairman, Dr Paul Tambyah, an expert on infectious diseases.
On Saturday (Feb 29), the Singapore Democratic Party uploaded the first part of APA: Covid-19 Edition on its Facebook page, with Dr Tambyah’s answers to the online questions. The doctor said the answers were given in his personal capacity and had no connection with any university or hospital.
Question from Su Hui: What should we consider to be a reliably good sign that the severity of the situation is diminishing? Is the rate of new infections a good indication?
Dr Tambyah: “Yes, the rate of new infections is a good indicator. If the rate of new infections is going down, that’s a sign that efforts are making progress and ideally, the rate of new infections should go to zero. For those of you who remember what happened during Sars, Singapore was not declared Sars-free until 14 days after the last new infection of Sars occurred in Singapore.”
Question from Niki Ng: Why are the elderly Covid-19 patients and patients with pre-existing illnesses, such as diabetes and cardiovascular disease have a higher chance of dying from this Covid-19 infection, than other patients who are younger and do not have any pre-existing illnesses?
Dr Tambyah: “The answer is relatively simple. The main reason is that just like other viral infections like influenza, if you have an underlying disease like chronic heart failure or chronic lung disease, then you are kind of living on the edge, and if you get a viral infection like influenza or worse, Covid-19, then that might tip you over the edge and create a lot of problems.”
He added that those people have fewer reserves, with weaker immune systems which make them more vulnerable to Covid-19 complications.
Another question from Niki Ng: The citizens of other countries, for instance, Thailand, Vietnam do eat wildlife such as bats, snakes, dogs, which similarly, the citizens of China are also eating. Why is it that the Covid-19 infection did not occur in Thailand and Vietnam, but it happened in China in December 2019?
Dr Tambyah: “I’ll have to be honest and tell you I don’t know. But the fact is that they have done genetic studies of this virus and they think it wasn’t multiple events.”
He explained that the virus occurred from a single event, and not through “multiple people eating multiple bats or pangolins which had the virus”.
The virus crossed from the animal into humans and took off explosively, said Dr Tambyah.
He mentioned the recent World Health Organization mission to China where they took samples from Wuhan, Hubei province and other parts of China, looking for different strains of flu such as bird flu. There was no evidence of the Covid-19 virus at all from the samples collected early in the year, said Dr Tambyah. “It just suddenly appeared at the end of 2019, and it continued to appear after that in the early part of this year.”
Question from Jennifer Su-mien Lim: What if the theory that the virus will abate/weaken with increasingly hot weather proves to be wrong. And how are medical professionals going to manage those who display symptoms of being re-infected? It will be very onerous on the workforce, to re-quarantine people again.
Dr Tambyah shared that he was “very sceptical” of the chances of re-infection because of how the virus operates.
He used as an example the woman in Japan who tested positive after being discharged and said that one possibility for that to occur was she continued virus shedding for a long time, even without symptoms. “We know this happens with other viral infections,” he said.
“The other possibility is that what they are detecting is not a live virus; in other words, we have no evidence that she spread the virus to anyone.” There have been cases, even in Singapore, where patients are well yet testing positive for the virus because it is still hanging around, and that is what’s picked up by the test, said the doctor.
He added that if re-infection were to happen, “medical professionals now are well-equipped into handling the case”.
Dr Tambyah gave another explanation as to why he thinks re-infection was highly unlikely. He said that discharged cases in China, Singapore and Europe had developed antibodies to the virus. “In other words, they are immune.” Much like chicken pox where people usually get it only once, the body builds up antibodies which serve as immunity to the virus.
Question from Rain Chang Hui Zi: Will we get infected with Covid-19 from a mosquito bite which had previously bitten a Covid-19 positive person?
Dr Tambyah also perceives the scenario to be highly unlikely because the virus thrives only in humans, maybe bats and other intermediate animals. “There is no evidence that this virus can survive in mosquitoes.”
Another reason he provided was that Covid-19 stays in the blood for a short period of time. He cited a case of a patient who passed away due to the virus. Medical experts looked for traces of the virus everywhere in the body and only found it in the lungs.
“Besides that, Covid-19 is occurring in very cold climates. Mosquitoes don’t do well in cold environments,” he said.
The SDP, along with Dr Tambyah, is accepting more questions to be answered for the second part of APA.
https://www.facebook.com/yoursdp/videos/2318029075161507/?v=2318029075161507
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